comminution

noun2

1. •
   The breaking or grinding up of a material to form smaller particles.

   • What circumstances determine the degree of comminution to which a substance should be subjected preparatory to future extraction? — 1873
2. •
   The fracture of a bone site into multiple pieces (at least three, and often many).

   • Comminution of the shaft of one or of both bones of the fore-arm does not of itself indicate operative interference, other complications may necessitate primary or secondary amputation. — 1851